Improved dry-dock



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JONATHAN RICHARDSON, OF GERMAN'IOWN, VIRGINIA.

i Letters Patent No. 87,291, dated February 23, 1369.

IMPROVED DRY-DOCK.

The Schedule referred to in these Latte-:s Patent and making part of the sameA Tu all whom tt may concern;

Be it known that I, J oNA'rHAN RICHARDSON, of Germantown, in the county of Fairfax, and State of Virginia, have invented a new and useful Improved Dry-Dock, and I do hereby declare the following to be a full, clear, and exact description thereof, sufiicient to enable those skilled in the art to which my invention appertains, to fully understand and use the same, reference being had to the accompanying drawings, forming part of this specification, and in which- Figure l, Sheet I,is anend elevation of my dry-dock, with a vessel on the ways, preparatory to the elevation of the vessel for repair.

Figure 2, Sheet I, a similar view, showing the vessel elevated.

Figure 3, Sheet II, is a side elevation of fig. 2.

My invention is an improved oating dry-dock, for elevating vessels for repairs. It can also be used to facilitate the passage of vessels over bars.

My object has been to improve the construction of dry-docks, so as to render them more simple, durable,

' and powerful, and capable of being worked with more economy of power than heretofore, and, at the same time, producing better results. To these ends,

My invention consists,

First, in hingin g air-tight tanks to the opposite sides of a central beam, which also forms the keel.

Second, in connection with the hinged tanks,'my invention consists in the employment of screws, so arranged, with relation to the hinged tanks, asto exert the most effective pressure thereon to sink them.

In order that others may so understand my improved: dry-dock as-tc be able to construct and use the same,

I will now proceed to describe it more fully in detail, with reference to the accompanying drawings, wherein similar letters indicate corresponding parts in the sevleral gures.

In the drawings- A represents a central bearing-beam, for the support of the vessel, and forming the keel ofthe dock, being made with a prow, A.

a a are eye-bolts, or brackets, fixed in the opposite sides of the beam A.

- Thesebolts or brackets, a, support metallic rods, b.

c c are rods hung loosely on the rods b, by means of eyes o. These rods c are formed with screw-threads on their outer ends.

B B represent air-tight tanks, provided with eyes d, through which the rods c pass loosely.

y B B represent tanks similar to those just described, but smaller, and hung in the same manner on the rods lc. These tanks are held in position by means of nuts e, and dat connecting-plates e', fitted on to the outer ends ofthe rods c. It will be observedthat similar series of the tanks B B are arranged on each side of the keel A.

l(l represents along plate of wood, resting on top the tanks B', and attached to -rods D, which are hooked on to the rods b, to form a hinge.

These plates constitute bearing-surfaces for screws E, which work through nuts f, swivelled to the horizontal beams F. (The screws E are not shown in iig. l.) These beams, when a vessel is in the dock, rest upon the deck of the same, and extend outward at each side, to a considerable distance from the vessel. The beams may be made double, as shown at 23, fig. 3, or single, as at 1 4, in'the same representation.

G represents screw-rods,- hinging on the fixedA rods at the sides of the keel A, and working through nuts y, swivelled to the beams F. I purpose making these nuts g adjustable longitudinally on the beams F, for a purpose to be hereinafter set forth.`

H H, lig. l, are screws, also working through nutsswivelled to the beams F, which are used to depress the tanks B B', to a certain extent.

I will now describe the mode of operating my drydoek.

In order to receive a vessel on the ways, it is necessary that the latter bel submerged to a level with the under side of the keel of the vessel. lThis is accomplished by unscrewing the nuts e, so as to lower the keel A, the parts being in the position represented iu fig. 1. When this has been lowered a sufficient distance, the vessel is readily placed on the ways, the beams F adj usted across the decks, the rods G brought up into contact with the sides, as shown, and the nuts y screwed down so as to hold the vessel securely. The screws H are now brought into the position represented in fg.1,bearing against the plate O, and turned in by any suitable-means. The tanks B B are thus gradually submerged, displacing the water, and thereby elevating the vessel. The screws H are only effective in depressing the tanks to ya certain degree, and when this point is reached, the outer series of screws is brought to bear, the inner series abandoned, and the operation of forcing down the tanks is continued until a body of Water equal to that formerly displaced by the vessel is displaced by the tanks, when, as a consequence, the vessel is lifted entirely from the water, and occupies the position shown in figs. 2 and 3. The upper surfaces of the tanks now form convenient platforms, on which the workmen may stand while engaged in caulking, painting, or otherwise repairing the vessel.4

To replace the vessel again in the water after repairs, the 'rods E are unscrewed, and as this progresses, the tanks will rise naturally, on account of their buoyancy, until the position shown in fig. 1 is resumed. The nuts e are now unscrewed, and the keel A descends until the vessel, freed from the restraint of rods and beams, is again afloat.

It will be 'observged that by varrangin g the depressingscrews, as described, they are brought to bear at the most effective. points on the tanks, the two mechanical powers, the lever and screw, being most ei'ectively combined. v

The advantages of my dry-dock will be at once appreciated by those acquainted with the dry-docks now in use. Hitherto, .floating dry-docks have been provided with tanks, which have been sind; by the Weight of water pumped into them, and then pumped out to raise the tanks. rlhis es, oi' course, a very slow operation, requiring a pumping-engine, and numerous `other appliances, together with a large force' oi' attendants to work them, thus entailing very heavy expenditures of money.

In `cout-i'zulistinction to all this, I. provide Heating dry-docks with air-tight tanks, conveniently arranged, and operated by means oi' screws, so situated as to exert, at all times, the most eii'ective pressure against the tanks, to depress them. Vith my dry-dock there is no pumping of water iirst into, then ont ofthe tanks, as they are depressed by means oi' screws, and elevated automatically, it only being necessary to relieve t-hem from the pressure of the screws.

I desire here to state that this dry-dock may be employed with excellent effect to assist the passage of deep-draught vessels in shallow Water, and over sand-bars, and other obstructions, the dock being operated the same as above described to raise the vessel, and then set in motion by any suitable means. trans`- porting the vessel to deep water.

The advantages of this are obvious, and will be especially appreciated in times of war.

By fitting the depressing-screws to Work through swivelled nuts, they are made capable oi' being turned up entirely out of the way.

Constructed as above described, a dry-dock is produced, which, for this class of structures, is remarkably simple, very durable, can be constructed at light comparative eipense, and can be effectively operated in muchv less time, and with i'ar greater economy, in men, money, and material, than those now in use.

Having thus described my invention,

that l' claim as new, and desire to secure by LettersPatent, is-

l. In a-'dry-dock or lighter, the air-tight tanks, hinged to the opposite sides of a central beznn or keel,

in described.

2. The air-tight tanks B B', loosely litted on the hinged rods c, and adjustable thereon, substantially as herein described, for the purpose set forth.

3. The double or single beams F, resting across the deck of the vessel, and connected with the ixedirods b by hinged screw-rods Gr, operating substantially as and for the purposes herein described.

4. The plate C, resting on the tanks, and hinged to the side-rods b, forming the bearing-surface for the screws E H, substantially as herein set forth.

5. The depressing-screws H E, fitted to the beams F, and arranged substantially as described, to exert pressure on the tanks, substantially as herein set forth.

(i. rlhe combination of the hinged tanks B B', the keel A, screw-rods G, beams F, and depressing-screws, all operating substantially as herein set forth.

To the above specilication of Amy d rydock, I have signed my name, this 13th day of Januar 1869, in the presence of two subscribing witnesses.

JONATHAN RICHARDSON.

Witnesses Guo. W. Ro'rnwnnr., SAMUEL S. BROWN.

substantially in the manner and l'or the purpose herei 

